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Comment by tifan | Hacker News Reader

Ah, this is used for loop detection by Huawei CPE.

Configuration reference: http://huawei.communicationsmuseum.org.uk/MA5616/clireferenc...

Would have been more fitting to use

  Algorhyme

  I think that I shall never see
  A graph more lovely than a tree.
  A tree whose crucial property
  Is loop-free connectivity.
  A tree that must be sure to span
  So packets can reach every LAN.
  First, the root must be selected.
  By ID, it is elected.
  Least-cost paths from root are traced.
  In the tree, these paths are placed.
  A mesh is made by folks like me,
  Then bridges find a spanning tree.
  -Radia Perlman

The author of this poem is actually the inventor of the Spanning Tree Protocol (which the poem describes): https://en.wikipedia.org/wiki/Radia_Perlman

P.S. For those who like nerdy poems, here's a poem which is a proof of the undecidability of the Halting Problem: http://ebiquity.umbc.edu/blogger/2008/01/19/how-dr-suess-wou...

https://teachinglondoncomputing.org/poetry/

But the modem is not made by Huawei. Its model number is G-140W-UD and it's made by Shanghai Nokia-Bell Co.,Ltd.

Could it be from the ISP-side devices?

It could be using Huawei software and hardware. Serbian ISP "Telekom Srbija" which uses mostly Huawei HG8245Q2 ONTs and has standardized on Huawei OLT and Core network, also uses these Nokia branded devices. AFAIK the Huawei GPON network is incompatible with other vendors which is why there's a small part of the capital city Belgrade stuck on old ZTE CPEs as that was a part of a pilot FTTH project with ZTE before China financed this rollout.

So, my point being, given they also use this exact Nokia ONT, it could very well mean that it's compatible with Huawei because it IS, in part, Huawei.

Thanks for the explanation! It certainly made more sense now :)

But why a poem and why THIS poem?

A shortish poem like this seems like a nice match. Ethernet has a minimum packet size, which is around the length of a line. The whole poem is short enough that you can remember it, but long enough that seeing a duplicate line would give you a good idea of having a network loop (possibly with delay) or having a second sender that started at an offset (although, maybe there's some ID information in the packet before the text begins).

This poem seems cute and memorable, and unlikely to offend any censors, and may have been available under a permissive license?

Could it be for trademark / copyright protection? There was an anti-spam mechanism in the past that worked this way. If you abused the system, they could sue you for millions. No idea if that is still around.

> Could it be for trademark / copyright protection?

Oracle uses this to connect SQL*Plus client to the database. This way, if you make a client without signing one their draconian contracts, they can sue you for infringing the copyrights on the poem.

Nintendo tried that and got slapped down hard.

Sega tried that with trademark law and they got slapped down hard.

That's the other (and arguably more interesting) part of the puzzle! :)

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